Supported high efficiency polyolefin catalyst component and methods of making and using the same

ABSTRACT

A supported high efficiency catalyst component for polyolefin production and methods of making and using the same are disclosed. A catalyst support made from a solid, particulate support material, a second solid material preferably substantially isostructural therewith and an organic electron donor compound is combined with a polymerization-active transition metal compound and optionally a second organic electron donor compound to form the catalyst component. Additionally, a dehydrating agent may be reacted with water in the solid, particulate support material in the production of the catalyst support. The methods of producing such a catalyst support and catalyst component are preferably performed by severe milling in the absence of any solvent. Such a catalyst produces polymer of such high quality and quantity that polymer extraction and polymer deashing are not necessary.

This is a continuation-in-part of application Ser. No. 146,341, filedMay 2, 1980 now U.S. Pat. No. 4,347, 158.

BACKGROUND OF THE INVENTION

The invention relates to a supported high efficiency catalyst forproduction of polyolefins and to the production of an improved supportfor these catalysts.

Organometallic compounds have been used in combination with transitionmetal compounds to catalyze the production of high molecular weightpolymers from ethylene and alpha-olefins to produce polymers having highstereoregularity.

The basic catalysts used in these methods are formed by combining atransition metal salt with a metal alkyl or hydride. Titaniumtrichloride and an aluminum alkyl, such as triethyl aluminum or diethylaluminum chloride, are often used. However, such catalysts generallyhave low productivity and produce polymer with low stereoregularity.

Isotactic polypropylene results from a head-to-tail linkage of themonomer units resulting in the asymmetric carbon atoms all having thesame configuration. The isotactic index is one measure of the percentageof isotactic isomer in the polymer formed. Atactic polypropylene resultsfrom random linkage of the monomer units. Isotactic polypropylene is ahighly useful commercial product having high tensile strength, hardness,stiffness, resilience, clarity and better surface luster. Polypropylenefinds extensive commercial use in injection molding, film, sheeting,filament and fiber applications. Commercially useful polypropylenecontains essentially the stereoregular or isotactic isomer.

For most applications, the polymer produced using these basic catalystsmust be extracted to remove the atactic (non-stereoregular) polymer toincrease the percentage of isotactic (stereoregular) polymer in thefinal product. It is also necessary to deash polymer produced by thismethod to remove access catalyst. The additional production steps ofpolymer extraction and polymer deashing add significantly to the cost ofpolymer produced with these basic catalysts.

The first improvement in these catalysts resulted from the use of mixedtitanium trichloride and aluminum trichloride as the catalyst with analuminum alkyl co-catalyst.

Later improvements centered on the supported catalysts. Many earlysupported catalysts were based on the reaction products of surfacehydroxyl containing compounds with transition metal compounds. Examplesinclude the reaction product of a transition metal compound with anhydroxy chloride of a bivalent metal, e.g., Mg(OH)Cl (British Pat. No.1,024,336), with Mg(OH)₂ (Belgian Patents 726,832; 728,002; and735,291), and with SiO₂, Al₂ O₃, ZrO₂, TiO₂, and MgO (British Pat. Nos.969,761; 969,767; 916,132; and 1,038,882).

Some later supported catalysts were based on the reaction products ofmagnesium alkoxides with transition metal compounds. Examples includethe reaction product of a transition metal compound with Mg(OR)₂ (U.S.Pat. No. 3,644,318 and Belgian Pat. Nos. 737,778; 743,325; and 780,530.)

Other supported catalysts were based on the reaction products ofmagnesium chloride with transition metal compounds. Titanium compoundswere reacted with MgCl₂ (U.S. Pat. No. 3,642,746 and Belgian Pat. Nos.755,185; 744,221; and 747,846).

Promoted catalysts result from the addition of certain Lewis bases(electron donors) to the catalyst system. The electron donor has incertain situations been combined with titanium trichloride duringproduction of the catalyst. Electron donors have included the ethers,esters, amines, ketones and nitroaromatics. Although the promotedcatalysts improved the isotactic index of the polymer, they generallystill did not produce polymer of such quality and quantity as to permitthe elimination of polymer extraction and polymer deashing to removecatalyst residue.

Recently, a catalyst component with sufficiently high yield toapparently eliminate the necessity for performing polymer deashing andpolymer extraction was described in U.S. Pat. No. 4,149,990. However,this catalyst was produced in solution, requiring catalyst washing.

SUMMARY OF THE INVENTION

The catalyst component of the present invention overcomes many of thedisadvantages of the above discussed prior art catalysts. Not only doesthe catalyst component of the present invention overcome thosedisadvantages associated with the polymerization of alpha-olefins toproduce satisfactory industrial polymers, but also a polymer withsuperior characteristics is produced. Further, the catalyst component ofthe present invention exhibits superior characteristics and is producedby a method not only offering significant economic advantages, but alsoreducing energy consumption and pollution, over the prior art.

The present invention provides a supported high efficiency catalystcomponent for use in the polymerization of olefins, particularlyalpha-olefins. Although the catalyst component has only been used in thehomo-production of propylene, ethylene and 1-butene, it is believed thatthe catalyst will also produce satisfactory homopolymers or co-polymersfrom other alpha-olefins and low molecular weight dienes.

The catalyst component of the present invention is produced byinterspersing a solid, particulate catalyst support material with asecond solid material, preferably substantially isostructural with theparticulate material. A titanium-free, solid, particulate catalystsupport is produced by reacting at least a portion of a first organicelectron donor compound with the second solid material at least on thesurface of the support, to reduce the surface area thereof. Apolymerization-active, transition metal compound, preferably a liquidtitanium compound, is bound at least on the surface of the support toproduce a solid, titanium-containing catalyst component. A secondorganic electron donor compound is optionally contacted with the supporteither before or simultaneously with the transition metal. Allcontacting of materials is preferably performed in the absence of asolvent or excess liquid reactant and in a vibratory or ball mill. Animproved, highly efficient catalystcomponent having a low specificsurface area, less than 1^(m2) /g, is produced.

DETAILED DESCRIPTION OF THE INVENTION

In order to obtain the high productivity and stereoregularity necessaryfor the formation of polymer with sufficiently high isotacticity andsufficiently low residue content to permit polymer use without polymerextraction or polymer deashing, it is presently believed that asupported catalyst component must be used.

It is believed that a solid, particulate support material which issubstantially isostructural with titanium compounds, possible permittingco-crystallization therewith, will provide the best support.

A solid, particulate support material selected from the group consistingof the Group IIA and IIIA salts and the salts of the multivalent metalsof the first transition series with the exception of copper forms thenucleus of the improved support. The magnesium and manganese saltsprovide what is currently believed to be the most useful solid,particulate support materials. The magnesium and manganese dihalides,alkyloxides, aryloxides and combinations thereof have been suggested inthe art to be satisfactory. Preferred support bases are M(OR)_(n)X_(2-n) where M is magnesium or manganese, R is alkyl or aryl, X is ahalide and n is 0, 1 or 2. Examples include MgCl₂, MgBr₂, MgI₂, MgF₂,Mg(OCH₃)₂, Mg(OCH₂ CH₃)₂, Mg(OC₆ H₅)₂ and combinations thereof. In thepreferred embodiment the magnesium dihalides, particular magnesiumdichloride, form the solid, particulate support material.

Magnesium dichloride is especially preferred as the support material dueto the high productivity of catalyst components using magnesiumdichloride and the less noxious nature of its residue in the producedpolymer.

Because the catalyst component is water and air reactive it is necessaryto insure that the water content of the solid, particulate supportmaterial is sufficiently low so as not to interfere with the catalyticactivity. For this reason, the magnesium dichloride used as the supportmaterial in the preferred embodiment should be anhydrous. Anhydrousmagnesium dichloride is prepared by drying under an HCl blanket for 4hours at a temperature of 350° C., or by any other conventional means.

In another feature of the present invention a dehydrating agent whichreacts with the water present to produce a volatile reaction productunder the reaction conditions and to produce a residue which is notdetrimental to alpha-olefin polymerization is employed. Such dehydratingagents include the silicon tetrahalides, calcium carbide and calciumhydride. These agents may be reacted, preferably by co-comminution in avibratory or ball mill, with a water containing solid, particulatesupport material prior to production of the catalyst component.

In the preferred embodiment, silicon tetrachloride has been used as aneffective dehydrating agent for this purpose. Silicon tetrachlorideeffectively dehydrated water-containing magnesium dichloride supportmaterials and surprisingly had no apparent effect on the activity of theresulting catalyst. It is preferred that only a quantity of dehydratingagent sufficient to react with the water present be used. The molarratio of silicon tetrachloride to water present in the support materialshould be about 0.5 to one.

In another feature of this invention the catalyst support comprising asolid, particulate support material together with at least the reactionproduct of any water contained therein and a dehydrating agent,preferably silicon tetrachloride, may be used with any conventionalmeans of supporting a polymerization-active transition metal compoundthereon. Co-communication in the absence of any solvent is preferred.Alternative solvent methods suffer from the requirement of additionalwash steps.

After this reaction, the resulting product may then be employed as thesolid, particulate catalyst support material in the production of anycatalyst component normally requiring anhydrous particulate supports,particularly anhydrous magnesium dichloride supports.

Another important feature of the present invention is the use of asecond solid material, also preferably isostructural with octahedraltitanium, in addition to the solid, particulate support material. Thismaterial is preferably different from but substantially isostructuralwith the solid, particulate support material. This second solid materialis preferably selected from the Group IIIA salts, particularly thehalides, phosphorus trichloride or phosphorus oxytrichloride. In thepreferred method of the present invention this second solid material isco-comminuted with the solid, particulate support material andoptionally the dehydrating agent. The aluminum trihalides, particularlyaluminum trichloride, are presently preferred as the second solidmaterial. The preferred molar ratio of support material to second solidmaterial, preferably magnesium dichloride to aluminum trichloride, isabout eight to 0.75-1-1.5.

When starting with an anhydrous solid, particulate support material thesupport material and the second solid material, preferably magnesiumdichloride and aluminum trichloride, are initially contacted, preferablyco-comminuted in a vibratory or ball mill or other similar mixingdevice. At least an intimate admixture of the magnesium dichloride andthe aluminum trichloride is formed and possibly a solid solution offormula MgCl₂.(1/X) AlCl₃ may be produced. The aluminum trichloride maybe acting as an agglomerating agent as the specific surface area of theadmixture or solid solution is rather low, generally about 4-6 m² /g.

An additional feature of the present invention is the association of afirst organic electron donor compound with this support to produce animproved support. It is believed that at least a portion of this firstelectron donor compound reacts with the second material to produce areaction product at least on the surface of the support. Formation ofthis product results in decreased specific surface area of the support,possibly by blocking of the pores of the support. The resulting supportgenerally has a specific surface area less than about 2 m² /g.Preferably at least one moiety of this electron donor compound willproduce a volatile reaction by-product under the reaction conditionswhen the electron donor compound reacts with the second solid material.Such moiety will often be an alkyl group containing less than sevencarbon atoms, preferably a methyl or ethyl group.

This electron donor compound may be chosen from organic compounds havingat least one atom of oxygen, sulfur, nitrogen or phosphorus to functionas the electron donor atom. Examples of such electron donors are ethers,esters, ketones, aldehydes, alcohols, carboxylic acids, phenols,thioethers, thioesters, thioketones, amines, amides, nitriles,isocyanates, phosphites and phosphines. The preferred electron donorcompounds are the aromatic ethers and the esters, particularly thealkylaryl ethers and the alkyl esters of carboxylic acids. Thissuperiority may be attributed to the presence of the pi electrons of thearomatic ring adjacent to the electron donor atoms. The preferred molarratio of solid, particulate support material to first electron donorcompound, in the preferred embodiment of magnesium dichloride toanisole, is about eight to 0.5-2.0, with about eight to 1-1.5 beingespecially preferred. The molar ratio of first electron donor compoundto second solid material should be about one to one.

As presently understood, methyl phenyl ether is the most effective firstelectron donor. This superiority may be accounted for by the low sterichindrance of the methyl group as well as its inductive effect inaddition to the previously discussed advantage of the aromatic ring.Further, a highly volatile methane derivative is formed on reaction ofmethyl phenyl ether with the second material. Although the exactreaction is not completely understood, it is believed that the etherlinkage --O-- associates with the aluminum of the support and at least aportion thereof reacts to produce a mixed phenoxide and a volatilemethyl chloride. See co-pending U.S. application Ser. No. 217,630,incorporated herein by reference. Although the complete reaction andstructure of the support is not presently understood, it is believedpossible that the reaction product of the methyl phenyl ether andaluminum trichloride may lower the specific surface area of the supportby blocking the pores in the magnesium dichloride support.

The method of the present invention contemplates preferably the initialco-comminution of the above three components to produce an improvedtitanium-free, catalyst support. Although it is possible to mix allthree components simultaneously, it has been found that better resultsare achieved by the initial interspersing of the solid, particulatesupport material and the second solid material, preferably magnesiumdichloride and aluminum trichloride, followed by the later addition andreaction of the organic electron donor compound, preferably methylphenyl ether. As stated above, a dehydrating agent, preferably silicontetrachloride, may be pre-mixed with the solid, particulate supportmaterial to react with and remove any undesired water.

In addition to the improved, titanium-free catalyst support produced bythe above method, the catalyst component of the present invention maycontain a second organic electron donor compound. This electron donorcompound may increase stereoregularity of the polymer by complexing orreacting with the particulate support and also associating with theactive transition metal compound to produce a rigid template upon whichthe polymer may form. This electron donor compound may be chosen fromthe same group as that of the first electron donor, and may be the sameor a different compound. However, it is believed for the same reasonsgiven above that the alkyl aryl ethers and the alkyl esters ofcarboxylic acids, but particularly the esters, provide the best results.In particular, the most effective catalyst components have been producedby using ethyl benzoate as the second electron donor.

The preferred molar ratio of solid, particulate support material tosecond electron donor compound, in the preferred embodiment of magnesiumdichloride to ethyl benzoate, is about eight to 0.5-1.5, or morepreferably about eight to 0.8-1.2. The second electron donor compoundshould preferably be added in excess relative to the active transitionmetal compound. Most preferably, the molar ratio of second electrondonor compound to active transition metal compound, in the preferredembodiment of ethyl benzoate to titanium tetrachloride, is about 1.6-2.4to one. This second electron donor compound may be added to and mixedwith the support prior to, during or after the addition of the activetransition metal compound. In another embodiment this second electrondonor compound may be precomplexed with the active transition metalcompound prior to the addition of the resulting complex to the enhancedsupport.

The final constituent of the catalyst component of the present inventionis an active tri, tetra-, or penta-valent transition metal compound ofthe Group IVB-VIB metals, preferably of the formula MO_(p) (OR)_(m)X_(n-2p-m). M is a Group IVB-VIB metal with valency n=3, 4 or 5. Themetals titanium, vanadium, chromium and zirconium are preferred.Presently it appears that titanium is the most preferred metal due toits superior productivity. O is oxygen. p is 0 or 1. R is an alkyl,aryl, cycloalkyl group or substituted derivative thereof, where O≦m≦n. Xis any halide, i.e., chloride, bromide, iodide or flouride, although thechloride is preferred. The choice of a particular transition metalcompound within the above formula will depend upon the reactionconditions and other constituents present in the catalyst. Some examplesof active transition metal compounds which may be used are TiCl₄,Ti(OCH₃)Cl₃, Ti(OCH₂ CH₃)Cl₃, VCl₃, VOCl₂, VOCl₃ and VO(OCH₃) Cl₂. Thepreferred active transition metal compound is liquid under the reactionconditions. The preferred active transition metal compound is a titaniumtetrahalide, and particularly titanium tetrachloride. The preferredmolar ratio of solid, particulate support material to active transitionmetal compound, in the preferred embodiment of magnesium dichloride totitanium tetrachloride, is about eight to 0.4-0.8, more preferably abouteight to 0.4-0.6.

It is presently believed that the active transition metal, preferablytetravalent titanium, is not reduced to the trivalent state in thecatalyst component. Rather, it is presently believed that this reductiontakes place in situ after addition of the organometallic compound duringpolymerization.

The preferred method of the present invention provides for the additionof the second organic electron donor compound, preferably ethylbenzoate, to the solid, particulate catalyst support and preferably theco-comminution thereof in a vibratory or ball mill. This step isfollowed by the addition of the active metal compound, preferablytitanium tetrachloride, to the resulting support and preferably furtherco-comminution. It is preferred to use an excess of the second organicelectron donor compound, preferably ethyl benzoate, in relation to theactive transition metal compound, preferably titanium tetrachloride.Although it is presently believed that this step-wise addition providesa superior catalyst, it is also contemplated that the active transitionmetal compound and the second electron donor may be preformed as acomplex prior to addition of the complex to the catalyst support andco-comminution therewith.

The interspersing and mixing of the various constituents of the catalystcomponent as discussed above is preferably performed in the absence ofany solvent. The final catalyst component contains substantially thesame quantity of active transition metal, preferably titanium, as wascontacted with the solid, particulate support during production of thecatalyst component. This preparation in the absence of any solventpermits the resulting catalyst component to be used without extractionor washing and results in considerable savings in catalyst productioncosts.

The preferred method of producing the above catalyst component comprisesthe co-comminution of the constituents under an inert atmosphere in avibratory or ball mill in the absence of any solvent. The solid,particulate support material is initally charged into the mill. If thesolid, particulate support material contains water which must beremoved, a sufficient quantity of dehydrating agent is initially addedto the particulate support material and the resulting mixtureco-comminuted at temperatures between about 0° C. and about 90° C. forfrom about 15 minutes to about 48 hours. Preferably this mixing is forfrom about 6 hours to about 24 hours, optimally for about 15 hours, attemperatures between about 35° C. and about 50° C.

Although co-comminution may take place at temperatures between about 0°C. and about 90° C. the preferred mixing temperature is from about 35°C. to about 50° C. Mixing times may range from about 15 minutes to about48 hours. Preferred mixing times are from about 12 hours to about 20hours, with optimal mixing at about 16 hours. Insufficient mixing willnot yield a homogeneous compound, while overmixing may causeagglomeration or may significantly decrease particle size of thecatalyst component, causing a direct reduction in particle size of thepolypropylene produced from the catalyst component.

In an alternative embodiment a solid, particulate support materialcontaining water, the dehydrating agent and the second solid materialare charged into the ball or vibratory mill together and co-comminutedat temperatures between about 0° C. and about 90° C. for from about 15minutes to about 48 hours. Preferably this mixing is for from about 12hours to about 20 hours, optimally about 16 hours, at temperaturesbetween about 35° C. and about 50° C.

A first electron donor compound is co-comminuted with the solid,particulate support material, second solid material and optionaldehydrating agent to produce the catalyst support. Mixing may be attemperatures between about 0° C. and about 90° C. for from about 30minutes to about 48 hours. The preferred mixing temperatures are fromabout 35° C. to about 50° C. for from about one hour to about 5 hours,although co-comminution for about 3 hours is optimal.

To the catalyst support produced as described above is added the activetransition metal compound. Although many transition metal compounds ofthe formula MO_(p) (OR)_(m) X_(n-2p-m) as described above will providesatisfactory catalyst components, liquid titanium tetrachloride is thepreferred active compound. Such an active transition metal compound isadded to the ball or vibratory mill and co-comminuted therein with thecatalyst support. This mixing may be at temperatures from about 0° C. toabout 90° C. and for from about 15 minutes to about 48 hours. It ispreferred that this mixing take place at temperatures ranging from about40° C. to about 80° C. and for from about 12 hours to about 20 hours,optimally for about 16 hours, to produce the supported high efficiencycatalyst component.

In an alternative embodiment of the invention a second electron donorcompound which may be different from or the same as the first electrondonor compound may be co-comminuted with the catalyst support prior toaddition of the active transition metal compound. In the preferredembodiment ethyl benzoate is co-comminuted in the ball or vibratory millwith the catalyst support at temperatures from about 0° C. to about 90°C. for from about 15 minutes to about 48 hours prior to addition oftitanium tetrachloride. However, the preferred mixing is at from about35° C. to about 50° C. for from about one hour to about 5 hours,optimally about 3 hours.

In another alternative embodiment of the invention, the second electrondonor compound, e.g., ethyl benzoate, may be premixed with the activetransition metal compound, e.g., titanium tetrachloride, prior toaddition of the resulting complex to the catalyst support. This complexis then mixed with the catalyst support under the conditions and for thetime specified above for the active transition metal compound.

The solid, titanium-containing catalyst component of the presentinvention, preferably obtained after co-comminution of the aboveingredients, exhibits superior characteristics to previously knowncatalyst components. Such a catalyst component is a supported highefficiency catalyst component for the polymerization of alpha-olefins.The catalyst component of the present invention has a very low specificsurface area, less than about 1^(m2) /g. Although the catalyst componentof the present invention should, like those of the prior art, be handledin an inert atmosphere in the absence of water, the fact that thiscatalyst component is less reactive and produces less noxiousdecomposition products than the catalyst components of the prior art,produces a safer catalyst component.

The solid catalyst component powder produced by the above method may bestored with little or no long term loss of activity.

It is presently believed that the active transition metal, preferablytetravalent titanium, is not reduced to the trivalent state in thecatalyst component. Rather, it is presently believed that this reductiontakes place in situ after addition of the organometallic compound duringpolymerization.

The catalyst component produced by the foregoing methods is used inconjunction with a co-catalyst of an organometallic compound andoptionally another organic electron donor compound to producestereoregular polyolefins. The organometallic co-catalyst is selectedfrom the group consisting of the alkyl aluminums, the alkyl aluminumhalides and the alkyl aluminum hydrides. The preferred co-catalysts arethe trialkyl aluminums, particularly triethyl aluminum and triisobutylaluminum, with triethyl aluminum especially preferred. The preferredmolar ratio of organometallic co-catalyst to titanium containingcatalyst component, preferably moles of triethyl aluminum to gram-atomsof Ti in the catalyst component of the present invention is about 50-300to one, most preferably about 240 to one. The organic electron donorcompound is selected from the same group as the electron donor compoundsof the titanium-containing catalyst component and may be the same ordifferent therefrom. Preferred electron donor compounds are selectedfrom the alkyl esters of the carboxylic acids such as ethyl anisate,methyl p-toluate or ethyl benzoate. The most preferred electron donorcompound is methyl p-toluate. The preferred molar ratio of electrondonor compound to titanium containing catalyst component, preferablymoles of methyl p-toluate to gram-atoms of Ti in the catalyst componentof the present invention is about 60-120 to one, most preferably about70-96 to one.

A catalyst produced by the foregoing method may be used in standardmethods for polymerization of alphaolefins. The catalyst may be used inliquid pool, inert solvent or gas phase preparations. Essentiallystandard operating conditions may be used in these variouspolymerization methods. When so used, the catalyst of the presentinvention produces polypropylene having an isotactic index of at least80, more preferably 90, and most preferably 93 or greater, a total ashcontent of not more than about 700 ppm, but more preferably as low asabout 300 ppm, and a magnesium residue of less than about 20 ppm.

The preferred means of using the catalyst of the present invention is inliquid pool polymerization. When so used, in the preparation ofpolypropylene, the expensive steps of polymer extraction, polymerdeashing and the associated solvent recovery are eliminated.

Most prior catalyst components have required an extraction step duringthe catalyst component manufacturing process. The catalyst component ofthe present invention, which may be produced in the absence of asolvent, eliminates such a step, and thereby drastically reduces notonly the capital costs for catalyst component manufacturing plants, butalso the operating manufacturing costs, while still producing a highlyactive catalyst component. Not only are these important economicadvantages achieved, but also significant reductions in energyconsumption and pollution are provided.

Another feature of the catalyst component support of the presentinvention provides other economic advantages. By using a dehydratingagent, the use of anhydrous magnesium chloride, more costly and moredifficult to handle and process, is eliminated.

The catalyst component of the present invention may also be sized inaccordance with various specifications, to achieve a polymer with fewerfine size particles, i.e. 200 mesh or less. This is important toreducing waste of polypropylene from loss of the fine powders and todecreasing handling problems associated with fine powders. Variations inthe milling times in the production of the catalyst component of thepresent invention permit the ability of achieving desired coarseness ofparticles of the catalyst component and thus of the produced polymer.

The catalyst of the present invention provides high productivity,yielding as high as from about 8,000 to about 18,000 pounds of polymerper pound of catalyst or from about 400,000 to about 900,000 pounds ofpolymer per pound of titanium. This increased productivity therebyreduces catalyst utilization. It further reduces catalyst residues inthe final polypropylene product, eliminating the need for polymerdeashing. The high isotacticity of the produced polymer also permits theelimination of the expensive step of polymer extraction and solventrecovery from polymer production processes using liquid monomer.

The catalyst of the present invention produces a highly stereoregularpolypropylene polymer with isotactic index generally greater than 90,preferably 93 or higher, and of low catalyst residue, total ash lessthan about 700 ppm and magnesium content less than about 20 ppm.Further, the polymer size distribution is such that generally less thanabout 5% of the produced polypropylene passes through a 140 mesh screen.These characteristics of the produced polymer permit the industrial useof the polymer without the expensive steps of polymer extraction andpolymer deashing, resulting in significant cost savings.

Hydrogen is often used to control the molecular weight of polymers. Inthe method of making polypropylene, the present catalyst componentproduces a polymer having a desirable molecular weight distribution atlower hydrogen pressures than generally used in other manufacturingprocesses.

EXAMPLES

The following examples illustrating certain embodiments of the presentinvention are intended only to illustrate the invention and are not tobe construed in any limiting sense. The polymer size distributions forpolypropylene produced wih the following catalysts are shown in TABLE I.

EXAMPLE 1

Anhydrous MgCl₂ was prepared by drying at 350° C. for 4 hours under anHCl blanket. 25 grams of this anhydrous MgCl₂, 4.34 grams AlCl₃ and 7.01grams anisole were charged under a nitrogen atmosphere into a vibratingball mill having a 0.6 liter capacity containing 316 stainless steelballs weighing a total of 3250 grams and having a diameter of 12 mm.This mixture was co-comminuted for 24 hours without temperature control.Titanium tetrachloride had been precomplexed with ethyl benzoate (EB) inn-heptane at about 50° C. 6.19 grams of this TiCl₄.EB complex was thencharged into the vibrating ball mill after the prior 24 hourco-comminution of the other materials, and the resulting mixtureco-comminuted for an additional 20 hours at ambient temperature andunder an inert atmosphere. This produced a solid catalyst componentwhich could be used, without requiring extraction or catalyst washing.

A sample of the solid catalyst so prepared was tested in the liquidpropylene polymerization test. 229 milligrams of the triethyl aluminum(TEAL) co-catalyst, 120 milligrams of methyl p-toluate (MPT) and 20milligrams of the catalyst component were charged into a 1.0 literstainless steel autoclave equipped with an agitator. Alternatively,dilute solutions of TEAL and MPT may be pre-complexed at temperaturesbelow about 25° C. for from about 5 minutes to about 10 minutes beforeaddition of the catalyst. The TEAL/Ti ratio was 240/1 and the TEAL/MPTratio was 2.5. 300 grams of liquid propylene was then charged into thereactor. Polymerization was accomplished at about 70° C. for about 1hour. At the end of this time any unreacted propylene was flashed offand the polypropylene produced was recovered.

156 grams of polypropylene was produced, giving a yield of 7800 gramspolypropylene per gram of catalyst or 390,000 grams polypropylene pergram of titanium.

To determine the isotactic index a fraction of the polymer was extractedwith boiling n-heptane for 16 hours in a Soxhlet Extractor and then-heptane insoluble fraction dried. The isotactic index of this polymerwas 86.0.

EXAMPLE 2

A catalyst, prepared according to the procedure of Example 1, was testedin the liquid propylene polymerization test as described in Example 1with a variation in the amount of methyl p-toluate employed. In thistest only 100 milligrams MPT were used, giving a TEAL/MPT ratio of 3.0.The productivity was 10,250 grams polypropylene per gram of catalyst or512,500 grams polypropylene per gram of titanium. However, the isotacticindex was only 69.0.

EXAMPLE 3

A catalyst, prepared according to the procedure of Example 1, was testedin the liquid polymerization test as described in Example 1 except that90 milligrams of ethyl anisate were substituted for the methyl p-toluatein the liquid propylene polymerization. The TEAL/EA ratio was 4.0. Theproductivity of the catalyst under these conditions was only 3750 gramspolypropylene per gram of catalyst or 187,500 grams polypropylene pergram of titanium with an isotactic index of 89.0.

EXAMPLE 4

A catalyst was prepared and tested using the same procedures asdisclosed in Example 1 except that 5.32 grams of anisole and 4.59 gramsof the TiCl₄.EB complex were used. The catalyst was tested according tothe method of Example 1 and showed a productivity of 5250 gramspolypropylene per gram of catalyst (262,500 grams polypropylene per gramof titanium) and an isotactic index of 81.3. CL EXAMPLE 5

A catalyst was prepared and tested using the same procedures asdisclosed in Example 1, except that 20.0 grams MgCl₂, 3.50 grams AlCl₃,2.84 grams anisole and 4.36 grams TiCl₄.EB complex were used. Thecatalyst exhibited a productivity of 4400 grams polypropylene per gramof catalyst (220,000 grams polypropylene per gram of titanium) and anisotactic index of 83.2.

                  TABLE I                                                         ______________________________________                                        Polymer Size Distribution                                                     (Percent polymer on mesh screen)                                                     Mesh                                                                   Example  20    40      80  140    200  325    Pan                             ______________________________________                                         4       54    25      17  3      0    0      0                                5       45    32      20  3      0    0      0                                6       51    20      14  7      5    3      1                                8       51    27      17  4      1    0      0                                9       40    27      24  7      2    0      0                               12       32    29      26  9      3    1      1                               13       43    29      22  5      1    0      0                               14       45    33      19  3      1    0      0                               16       23    25      28  13     7    4      1                               17       40    26      23  8      2    1      0                               19       38    26      22  9      3    1      1                               20       41    25      23  1      3    1      0                               21       31    26      26  12     4    1      0                               22       37    27      25  8      2    1      0                               23       37    28      25  7      2    1      0                               24       43    25      21  8      2    1      1                               25       38    30      24  5      2    1      1                               26       42    26      19  7      4    2      1                               28       50    27      18  5      2    1      0                               29       51    24      14  5      3    2      1                               31       63    20      13  3      1    0      0                               32       78    15       6  1      0    0      1                               38 (7 hr)                                                                              44    18      21  9      5    3      2                               38 (10 hr)                                                                             59    22      15  3      1    1      0                               ______________________________________                                    

EXAMPLE 6

A catalyst was prepared and tested using the same procedures asdisclosed in Example 1, except that 30.0 grams MgCl₂, 3.00 grams AlCl₃,4.87 grams anisole and 6.26 grams TiCl₄.EB complex were used. Thecatalyst exhibited a productivity of 3900 grams polypropylene per gramof catalyst (195,000 grams polypropylene per gram of titanium) and anisotactic index of 90.2.

EXAMPLE 7

A catalyst was prepared and tested using the same procedures asdisclosed in Example 1, except that 20.0 grams MgCl₂, 1.17 grams AlCl₃,2.84 grams anisole and 4.05 grams TiCl₄.EB complex were used. Thecatalyst exhibited a productivity of 2800 grams polypropylene per gramof catalyst (140,000 grams polypropylene per gram of titanium) and anisotactic index of 85.6.

EXAMPLE 8

A catalyst was prepared by a procedure similar to that disclosed byExample 1 and tested by the procedure disclosed by Example 2. 30 gramsMgCl₂, 5.25 grams AlCl₃ and 3.53 grams anisole were co-comminuted for 10hours. 6.41 grams TiCl₄.EB complex were added and co-comminutioncontinued for 20 hours. The yield was 3900 grams polypropylene per gramof catalyst (195,000 grams polypropylene per gram of titanium) with anisotactic index of 92.4.

EXAMPLE 9

A catalyst was prepared and tested as in Example 8 except that theanhydrous MgCl₂ was not HCl dried and the initial milling time was 15hours. The yield was 4800 grams polypropylene per gram of catalyst(240,000 grams polypropylene per gram of titanium) with an isotacticindex of 91.9.

EXAMPLE 10

A catalyst was prepared and tested as in Example 9 except that 3.50grams AlCl₃, 8.37 grams anisole, and 7.00 grams TiCl₄.EB were used. Theyield was only 1100 grams polypropylene per gram of catalyst (55,000grams polypropylene per gram of titanium) with an isotactic index of92.0.

EXAMPLE 11

A catalyst was prepared and tested as in Example 9 except that the millwas heated to about 90° C. before the addition of the TiCl₄.EB complex.The yield was 4250 grams polypropylene per gram of catalyst (212,500grams polypropylene per gram of titanium) with an isotactic index of88.5.

EXAMPLE 12

A catalyst was prepared and tested as in Example 9 except that the finalmilling time was also 15 hours. The yield was 4900 grams polypropyleneper gram of catalyst (245,000 grams polypropylene per gram of titanium)with an isotactic index of 92.8.

EXAMPLE 13

A catalyst was prepared and tested as in Example 12 except that 7.05grams anisole and 7.00 grams TiCl₄.EB complex were used. The yield was4000 grams polypropylene per gram of catalyst (200,000 gramspolypropylene per gram of titanium) with an isotactic index of 93.4.

EXAMPLE 14

A catalyst was prepared and tested by a procedure similar to thatdisclosed in Example 9 except that the final milling time was also 10hours. 28.7 grams anhydrous MgCl₂, 6.52 grams AlCl₃, 5.28 grams anisoleand 6.70 grams TiCl₄.EB complex were used. The yield was 3450 gramspolypropylene per gram of catalyst (172,500 grams polypropylene per gramof titanium) with an isotactic index of 94.0.

EXAMPLE 15

A catalyst was prepared and tested as in Example 14 except that 22.0grams MgCl₂, 7.89 grams AlCl₃, 3.53 grams anisole and 5.55 gramsTiCl₄.EB complex were used and the mill was heated to about 90° C.before addition of the TiCl₄.EB. The yield was 2000 grams polypropyleneper gram of catalyst (100,000 grams polypropylene per gram of titanium)with an isotactic index of 87.7.

EXAMPLE 16

Anisole and AlCl₃ were pre-complexed and 6.34 grams of this complexco-comminuted with 20.0 grams anhydrous MgCl₂ for 24 hours in the millof Example 1. 4.36 grams TiCl₄.EB complex were added to the mill andco-comminuted for an additional 20 hours. The catalyst, when tested asin Example 1, showed a yield of 2319 grams polypropylene per gram ofcatalyst (115,950 grams polypropylene per gram of titanium) with anisotactic index of 92.6.

EXAMPLE 17

30.0 grams anhydrous MgCl₂, 5.25 grams AlCl₃ and 3.53 grams anisole wereco-comminuted for 15 hours as in Example 1. 3.19 grams ethyl benzoatewere added to the mill and the resulting mixture co-comminuted for anadditional 10 hours. Finally, 4.00 grams TiCl₄ were added to the milland co-comminution resumed for an additional 15 hours. The catalyst,tested as in Example 2, showed a yield of 3800 grams polypropylene pergram of catalyst (190,000 grams polypropylene per gram of titanium) withan isotactic index of 92.7.

EXAMPLE 18

A catalyst was prepared and tested as in Example 17 except that thefinal milling time was only 10 hours. The yield was 2050 gramspolypropylene per gram of catalyst (102,500 grams polypropylene per gramof titanium) with an isotactic index of 92.7.

EXAMPLE 19

A catalyst was prepared and tested as in Example 17 except that 5.17grams of ethyl benzoate were added to and co-comminuted with theenhanced support for only 5 hours, followed by addition of 3.78 gramsTiCl₄ and co-comminution for 15 hours. The yield was 5500 gramspolypropylene per gram of catalyst (275,000 grams polypropylene per gramof titanium) with an isotactic index of 92.4.

EXAMPLE 20

A catalyst was prepared and tested as in Example 19 except that the millwas heated to about 90° C. after the addition of TiCl₄. The yield wasreduced to 3500 grams polypropylene per gram of catalyst (175,000 gramspolypropylene per gram of titanium) with an isotactic index of 92.7.

EXAMPLE 21

A catalyst was prepared and tested as in Example 19 except that theco-comminution time after addition of ethyl benzoate was only 4 hoursand the co-comminution time after addition of TiCl₄ was increased to 16hours. The yield was only 3700 grams polypropylene per gram of catalyst(185,000 grams polypropylene per gram of titanium) with an isotacticindex of 93.2.

EXAMPLE 22

A catalyst was prepared and tested as in Example 21 except that 5.89grams ethyl benzoate and 3.83 grams TiCl₄ were used. The yield was 3750grams polypropylene per gram of catalyst (187,500 grams polypropyleneper gram of titanium) with an isotactic index of 94.5.

EXAMPLE 23

A catalyst was prepared and tested as in Example 19 except that themilling time after addition of ethyl benzoate was only 2 hours and themill was heated to about 90° C. prior to addition of the ethyl benzoate.The yield was 3400 grams polypropylene per gram of catalyst (170,000grams polypropylene per gram of titanium) with an isotactic index of94.3.

EXAMPLE 24

A catalyst was prepared and tested as in Example 17 except that 4.58grams anisole were used, 5.89 grams ethyl benzoate were used andco-comminuted for only 2 hours and finally 3.94 grams TiCl₄ were addedand co-comminuted for 16 hours. The yield was 4100 grams polypropyleneper gram of catalyst (205,000 grams polypropylene per gram of titanium)with an isotactic index of 93.7.

EXAMPLE 25

30.0 grams anhydrous MgCl₂ and 5.25 grams AlCl₃ were co-comminuted for16 hours as in Example 1. 5.89 grams ethyl benzoate were added to themill and the resulting mixture co-comminuted for an additional 4 hours.Finally, 3.50 grams TiCl₄ were added to the mill and co-comminuted foran additional 15 hours. The catalyst, tested as in Example 2, showed ayield of only 1750 grams polypropylene per gram of catalyst (87,500grams polypropylene per gram of titanium) with an isotactic index of88.4.

EXAMPLE 26

30.0 grams anhydrous MgCl₂ and 3.00 grams anisole were co-comminuted for4 hours as in Example 1. 5.18 grams ethyl benzoate were added to themill and the resulting mixture co-comminuted for an additional 15 hours.Finally, 3.30 grams TiCl₄ were added to the mill and co-comminutionresumed for an additional 15 hours. The catalyst, tested as in Example2, showed a yield of 4100 grams polypropylene per gram of catalyst(205,000 grams polypropylene per gram of titanium) with an isotacticindex of 91.2.

EXAMPLE 27

3.0 grams anhydrous MgCl₂ was directly co-comminuted with 5.18 gramsethyl benzoate for 15 hours as in Example 1. 3.09 grams TiCl₄ was addedto the mill and the resulting mixture co-comminuted for an additional 15hours. The catalyst, when tested as in Example 2, showed a yield of only3000 grams polypropylene per gram of catalyst (150,000 gramspolypropylene per gram of titanium) with an isotactic index of 90.6.

EXAMPLE 28

30.0 grams anhydrous MgCl₂ containing 6.63% H₂ O were co-comminutedunder a nitrogen atmosphere with 7.01 grams SiCl₄ for 16 hours in themill of Example 1. 5.25 grams AlCl₃ and 3.53 grams anisole were added tothe mill and co-comminuted for an additional 15 hours. 5.17 grams ethylbenzoate were added and co-comminuted for an additional 5 hours.Finally, 4.45 grams TiCl₄ were added and co-comminuted for an additional15 hours. The catalyst, tested as in Example 2, showed a yield of only3600 grams polypropylene per gram of catalyst (180,000 gramspolypropylene per gram of titanium) with an isotactic index of 91.1.

EXAMPLE 29

A catalyst was prepared and tested as in Example 28 except that theinitial milling time was only 15 hours and the milling time followingaddition of ethyl benzoate was only 3 hours. The yield was reduced to1850 grams polypropylene per gram of catalyst (92,500 gramspolypropylene per gram of titanium) with an isotactic index of 90.5.

EXAMPLE 30

A catalyst was prepared and tested as in Example 28 except that 14.03grams SiCl₄ was used and the milling times were respectively, 18 hours,17 hours, 2 hours and 15 hours. The yield was only 2250 gramspolypropylene per gram of catalyst (112,500 grams polypropylene per gramof titanium) with an isotactic index of 90.8.

EXAMPLE 31

A catalyst was prepared and tested as in Example 28 except that theMgCl₂ had only a 0.35% H₂ O content, only 1.00 grams SiCl₄ were used,3.87 grams TiCl₄ were used and the milling times were respective, 4hours, 15 hours, 3 hours and 15 hours. The yield was 5900 gramspolypropylene per gram of catalyst (295,000 grams polypropylene per gramof titanium) with an isotactic index of 94.5. Liquid pool polymerizationtests using this catalyst under different hydrogen pressures todetermine the effect of hydrogen pressure or productivity, isotacticindex and melt flow were also conducted. The results of these tests areshown in TABLE II.

EXAMPLE 32

Anhydrous MgCl₂ was prepared by drying at 350° C. for 4 hours under anHCl blanket. 2500 grams of this anhydrous MgCl₂ and 438 grams AlCl₃ werecharged under a nitrogen atmosphere into a Vibratom mill having acapacity of 10.0 liters and containing 2,250 stainless steel ballsweighing a total of 144 kilograms and each having a diameter of oneinch. This mixture was co-comminuted for 16 hours at 35°-70° C. 294grams anisole was added and co-comminution continued for 3 hours at 35°C. 493 grams ethyl benzoate were added and co-comminuted for anadditional 3 hours at 35° C. Finally, 320 grams TiCl₄ were added andco-comminuted for 16 hours at 62° C.

The catalyst, tested as in Example 2, showed a yield of 8000 gramspolypropylene per gram of catalyst (400,000 grams polypropylene per gramof titanium) with an isotactic index of 95.6. Additional tests under ahydrogen atmosphere to determine the effect of hydrogen pressure onproductivity, isotactic index and melt flow are shown in TABLE II.Polymer residues for several inorganics are shown in Table III.

                  TABLE II                                                        ______________________________________                                        Effect of Hydrogen Pressure                                                   During Polymerization                                                                        Liquid Pool                                                                              Isotactic                                                  Hydrogen                                                                              Productivity                                                                             Index    Melt Flow                                         (psig)  (g PP/g Cat.)                                                                            (%)      (dg/M)                                     ______________________________________                                        EXAMPLE  0         6000       94.5   0.4                                      31       5         7500       93.4   0.7                                               10        7250       92.7   1.8                                               15        7200       92.4   4.2                                               20        5500       92.3   4.0                                               25        5900       91.0   10.4                                              35        6200       90.5   26.6                                     EXAMPLE  0         8000       95.6   0.18                                     32       5         8900       93.9   1.25                                              10        7900       93.3   3.68                                              15        8300       92.2   3.81                                              25        8650       92.0   14.58                                             35        9800       89.0   30.92                                    ______________________________________                                    

                  TABLE III                                                       ______________________________________                                        Polymer Residue for                                                           Example 32                                                                    Liquid Pool Total                                                             Productivity                                                                              Ash     Mg        Ti    Al                                        (g PP/g Cat.)                                                                             (ppm)   (ppm)     (ppm) (ppm)                                     ______________________________________                                        8900        590     18        3     220                                       8300        642     15        2     310                                       8650        465     15        3     245                                       9800        630     15        3     325                                       ______________________________________                                    

Catalyst components prepared according to the method of Example 32 havebeen analyzed for specific surface area by the B.E.T. method. Thespecific surface area is low, less than one square meter per gram.Representative specific surface areas of catalyst components preparedaccording to the method of Example 32 are 0.64, 0.80 and 0.94 m² /g.

These areas were determined using nitrogen. Other catalyst componentsprepared in the same way were analyzed for specific surface area usingrespectively nitrogen and krypton. Specific surface areas determinedwith nitrogen were 0.55, 0.85, 0.62 and 0.79 m² /g; those determinedwith krypton were 0.25, 0.40, 0.28 and 0.26 m² /g.

In a further example, specific surface areas were determined at varioussteps in the preparation of a catalyst component according to theprocedure of Example 32. The specific surface area after theco-comminution of magnesium dichloride and aluminum trichloride was 4-6m² /g. After co-comminution with anisole, the specific surface area wasreduced and measured 1.25 and 1.65 m² /g. After further co-comminutionwith ethyl benzoate, the specific surface area was further reduced andmeasured 0.62 and 0.72 m² /g. Finally, after co-comminution withtitanium tetrachloride, the specific surface area was measured as 0.76m² /g.

EXAMPLE 33

A sample of the solid catalyst component prepared according to theprocedure of Example 32, was tested in the high pressure heptanepolymerization test. 500 milliliters of heptane was charged into a 1.0liter stainless steel autoclave equipped with an agitator. 290milligrams of triethyl aluminum (TEAL) was introduced and after stirringat 20° C. for 3 minutes, 120 milligrams of methyl-p-toluate (MPT) wasintroduced and stirred therewith at 20° C. for 3 minutes. 20 milligramsof the catalyst component prepared according to the procedure of Example32 was then added. 81 milliliters of hydrogen at STP and propylene (150psig) were then added and the temperature raised to 70° C.Polymerization was accomplished at 70° C. for about 2 hours. At the endof this time the unreacted propylene was vented and the polypropyleneproduced was recovered by filtration. The amount of polymer soluble inthe polymerization solvent was determined by evaporation of an aliquotof the solvent. The catalyst produced 7155 grams polypropylene per gramof catalyst (357,750 grams polypropylene per gram of titanium) with anisotactic index of 93.8 and a heptane soluble of 2.7%.

In a second test, 162 milliliters of hydrogen at STP was used. Thecatalyst produced 6075 grams polypropylene per gram of catalyst (303,750grams polypropylene per gram of titanium) with an isotactic index of90.0 and a heptane insoluble of 4.4%.

EXAMPLE 34

A catalyst was prepared as in Example 32 but using commerciallyavailable anhydrous magnesium dichloride. The amounts of AlCl₃, anisoleand ethyl benzoate were also varied. 2,500 grams commercially availableanhydrous MgCl₂ and 656 grams AlCl₃ were co-comminuted for 16 hours at30° C. 443 grams anisole were added and co-comminution continued for 3hours at 30° C. 739 grams ethyl benzoate were added and co-comminutioncontinued for an additional 3 hours at 30° C. Finally, 319 grams TiCl₄were added and the mixture co-comminuted for 16 hours at 60° C.

The catalyst, tested as in Example 32 but using 88 milligrams MPT and 10psi hydrogen, showed a high yield of 11,300 grams polypropylene per gramof catalyst (642,000 grams polypropylene per gram of titanium) with anisotactic index of 92.7. The polymer residuals were 13 ppm magnesium, 2ppm titanium, 227 ppm aluminum and 586 ppm total ash.

EXAMPLE 35

A catalyst was prepared and tested as in Example 32. 2500 grams MgCl₂having a water content of 1.17%, 275 grams SiCl₄ and 656 grams AlCl₃were charged into the mill and co-comminuted for 16 hours at 40° C. 393grams anisole were added and co-comminution continued for 3 hours at 45°C. 494 grams ethyl benzoate were added and co-comminution continued foran additional 3 hours at 48° C. Finally, 321 grams TiCl₄ were added andthe mixture co-comminuted for 16 hours at 58° C. When tested under 15psig H₂ this catalyst produced 8000 grams polypropylene per gram ofcatalyst (400,000 grams polypropylene per gram of titanium) with anisotactic index of 89.9.

EXAMPLE 36

2660 grams of MgCl₂ containing 4.98% water and 1036 grams SiCl₄ werecharged under a nitrogen atmosphere into the Vibration mill of Example32. This mixture was co-comminuted for 21.5 hours at 35° C. 466 gramsAlCl₃ was added to the mill and contents and co-comminuted for 1.0 hourat 35° C. 313 grams anisole was added and co-comminution continued for19.5 hours at 35° C. 525 grams ethyl benzoate was added and the mixtureco-comminuted for 5.0 hours at 35° C. Finally, 341 grams TiCl₄ was addedand co-comminuted at 35° C. for 19.0 hours. A sample was taken and themixture co-comminuted an additional 6.0 hours.

The catalyst of the first sampling, tested as in Example 2, showed ayield of 3650 grams polypropylene per gram of catalyst (182,500 gramspolypropylene per gram of titanium) with an isotactic index of 93.4. Thecatalyst of the second sampling showed a yield of only 2550 gramspolypropylene per gram of catalyst (127,500 grams polypropylene per gramof titanium) with an isotactic index of 94.2.

EXAMPLE 37

A catalyst was prepared and tested as in Example 35, except that theMgCl₂ contained only 1.17% water and only 185 grams SiCl₄ were used. 369grams AlCl₃, 249 grams anisole, 416 grams ethyl benzoate and 271 gramsTiCl₄ were substituted for the quantities of Example 35.

The polymerization results were identical to those of Example 36.

EXAMPLE 38

5000 grams of MgCl₂ containing 1.17% water and 552 grams SiCl₄ werecharged under a nitrogen atmosphere into the Vibratom mill of Example32. This mixture was co-comminuted for 16.0 hours at 28°-55° C. 875grams AlCl₃ was added to the mill and contents and co-comminuted for 1.0hour at 28°-55° C. 588 grams anisole was added and co-comminutioncontinued for 3.0 hours at 53°-63° C. 986 grams ethyl benzoate was addedand the mixture co-comminuted for 3.0 hours at 53°-63° C. 640 gramsTiCl₄ was added and co-comminuted at 63° C. for an additional 7.0 hours,3.0 hours, 4.0 hours and finally 3.0 hours, with a sample of catalystcomponent taken for testing after each time.

The catalyst was tested as in Example 2, except that 25 psig hydrogenwas present in the autoclave. The productivity and isotactic index areshown in TABLE IV.

                  TABLE IV                                                        ______________________________________                                        Liquid Pool Polymerization                                                                       Productivity                                                       TiCl.sub.4 (g.PP/g  (g.PP/g                                                   milling time (hrs)                                                                       Cat.)    Ti)      II (%)                                   ______________________________________                                        EXAMPLE 38                                                                               7.0 (25 psig H)                                                                           4800     240,000                                                                              90.0                                             10.0 (25 psig H)                                                                           5850     292,500                                                                              91.1                                             14.0 (25 psig H)                                                                           5800     290,000                                                                              90.2                                             17.0 (25 psig H)                                                                           5750     287,500                                                                              91.0                                             17.0 (no H.sub.2)                                                                          4750     237,500                                                                              95.6                                   EXAMPLE 39                                                                               7.0 (no H.sub.2)                                                                          2500     125,000                                                                              96.3                                             10.0 (no H.sub.2)                                                                          3600     180,000                                                                              95.6                                             13.0 (no H.sub.2)                                                                          4250     212,500                                                                              94.1                                             18.0 (no H.sub.2)                                                                          4750     237,500                                                                              93.8                                             23.0 (no H.sub.2)                                                                          3500     175,000                                                                              94.5                                   ______________________________________                                    

EXAMPLE 39

A catalyst was prepared and tested as in Example 35 with the quantity ofmaterials the same as there except that only 2500 grams MgCl₂ were used.The milling times and temperatures were changed to 5.0 hours at 35°-70°C. for the MgCl₂ and SiCl₄, 1.0 hour at 35° C. after addition of AlCl₃,3.0 hours at 35°-70° C. after addition of anisole and 3.0 hours at35°-70° C. after addition of ethyl benzoate. Milling after addition ofTiCl₄ was at 35°-70° C. and catalyst component samples were taken after7.0, 10.0, 13.0, 18.0 and 23.0 hours.

Polymerization test results are shown in TABLE IV.

EXAMPLE 40

2500 grams MgCl₂ containing 0.16% water and 37 grams SiCl₄ were chargedunder a nitrogen atmosphere into the Vibratom mill of Example 32. Thismixture was co-comminuted for 5.0 hours at 52° C. 438 grams AlCl₃ wasadded and co-comminuted for 1.0 hour at 60° C. 294 grams anisole wasadded and co-comminuted for 3.0 hours at 70° C. 494 grams ethyl benzoatewas added and co-comminuted for 3.0 hours at 75° C. Finally, 323 gramsTiCl₄ was added and co-comminuted at 92° C. for 18.0 hours and sampled,followed by an additional co-comminution at 32° C. for 1.0 hour.

The catalyst was tested as in Example 38. Productivity of the firstsample was 4600 grams polypropylene per gram of catalyst (230,000 gramspolypropylene per gram of titanium) with an isotactic index of 87.2. Thesecond sample showed a productivity of 5100 grams polypropylene per gramof catalyst (255,000 grams polypropylene per gram of titanium) with anisotactic index of 93.9.

EXAMPLE 41

A sample of a solid catalyst component prepared according to theprocedure of Example 32 was tested in the polymerization of ethylene. Aone liter jacketed and magnetically stirred autoclave was maintained at25° C. and under an ethylene purge. 194 milligrams of triethyl aluminum(TEAL) was introduced to the autoclave followed by 16 milligrams of thecatalyst component prepared according to the procedure of Example 32.The catalyst component was introduced as a 40 milligram per milliliterdispersion in mineral oil. The autoclave was pressurized to 65 psig withhydrogen. 500 milliliters of isobutane followed by ethylene werepressurized into the reactor and the contents brought to a totalpressure of 500 psig at 85° C. The polymerization was terminated afterone hour, the isobutane and unreacted ethylene was vented and thepolyethylene produced was recovered.

The catalyst produced 9,700 grams polyethylene per gram of catalyst(485,000 grams polyethylene per gram of titanium). The melt index of thepolymer was 3.1 grams per ten minutes, the density 0.9694 grams per ccand the Mw/Mn ratio 6.2.

EXAMPLE 42

The polymerization of Example 41 was repeated except that thepolymerization was conducted for four hours. The catalyst produced20,800 grams polyethylene per gram of catalyst (1,040,000 gramspolyethylene per gram of titanium) during four hours. The catalystproductivity was 5,200 grams polyethylene per gram of catalyst per hour(260,000 grams polyethylene per gram of titanium per hour). The meltindex of the polymer was 8.8 grams per ten minutes, the density 0.9666grams per cc and the Mw/Mn ratio 4.9.

EXAMPLE 43

The polymerization of Example 41 was repeated except that triisobutylaluminum (TIBAL) was used as the cocatalyst in place of triethylaluminum, 20 milligrams of the catalyst component prepared according tothe procedure of Example 32 was used and the hydrogen pressure was 50psig.

The catalyst produced 7,300 grams polyethylene per gram of catalyst(365,000 grams polyethylene per gram of titanium). The melt index of thepolymer was 0.9 grams per ten minutes, the density 0.9593 grams per ccand the Mw/Mn ratio 5.0.

EXAMPLE 44

A catalyst was prepared according to the procedure of Example 1 andtested in the bulk polymerization of 1-butene. 229 milligrams TEAL, 100milligrams MPT and 20 milligrams of the catalyst were introduced into aone liter autoclave equipped with an agitator. The autoclave waspressurized with 10 psi hydrogen and then charged with 500 millilitersof 1-butene. Polymerization was conducted at 40° C. for 2 hours. At theend of this time unreacted 1-butene was flashed off and the polybuteneproduced was recovered.

The catalyst produced 64 grams polybutene, giving a yield of 3,200 gramspolybutene per gram of catalyst. When extracted by boiling diethyl etherfor 16 hours in a soxhlet extractor, the ether insoluble fractionrepresented 94.4 percent of the polymer produced.

In view of the preceding description and examples, further modificationsand alternative embodiments of the present invention should be apparentto those skilled in the art. For example, it may be preferable to slowlyadd the liquid reactants, such as methyl phenyl ether, ethyl benzoate,and titanium tetrachloride, in a metered spray during the initial 30-60minutes of the respective co-comminution stages in order to avoidforming a paste-like mixture of ingredients. Accordingly, the precedingdescription and examples are to be construed as explanatory andillustrative only and are for the purpose of teaching and enabling thoseskilled in the art to practice this invention.

While the preferred embodiment is to be understood to be the best modepresently contemplated, it is by no means the only embodiment possible.It will be apparent to those skilled in the art that many modificationsand changes in this specific method and composition may be made withoutdeparting from the scope and spirit of the present invention. Forexample, the disclosed catalyst may be suited for polymerizing olefinsother than alpha-olefins. Also, supports other than magnesium chlorideand active transition metal compounds other than titanium tetrachloridemay become commercially feasible. It is applicant's intention in thefollowing claims to cover such modifications and variations as fallwithin the true spirit and scope of the invention.

What is claimed is:
 1. A method for producing a catalyst supportsuitable for use in alpha-olefin polymerization comprising:providing atitanium-free, first particulate material suitable for use inalpha-olefin polymerization, the first particulate material beingselected from the group comprising the Group IIA and IIIA salts and thesalts of the multivalent metals of the first transition series with theexception of copper; interspersing a second solid material with saidfirst particulate material to form a titanium-free, particulate supportadmixture, said second solid material being different from butsubstantially isostructural with said first particulate material andbeing selected from the group comprising the Group IIIA salts; and thenapplying an organic electron donor compound to said particulate supportadmixture and reacting at least a portion of said electron donorcompound with said second solid material on at least the surface of saidparticulate support admixture to produce a titanium-free, solid,particulate catalyst support having a specific surface area less thanthe specific surface area of said particulate support admixture.
 2. Themethod of claim 1, wherein said first particulate material is selectedfrom the group consisting of magnesium dihalides and manganesedihalides.
 3. The method of claim 2, wherein said titanium-free, solid,particulate catalyst support has a surface area less than about twosquare meters per gram.
 4. The method of claim 3, wherein said firstparticulate material is magnesium dichloride, said second solid materialsubstantially isostructural therewith is aluminum trichloride, and saidorganic electron donor compound is anisole.
 5. A method of producing acatalyst component suitable for use in alpha-olefin polymerizationcomprising:(a) producing a titanium-free, solid particulate catalystsupport comprising:(i) a magnesium or manganese dihalide; (ii) a secondmaterial interspersed with said magnesium or manganese dihalide, thesecond material being capable of reacting with an organic electron donorcompound to form a reaction or addition product and being selected fromthe group comprising the Group IIIA salts; and (iii) a first organicelectron donor compound, at least a portion of which reacts with atleast a portion of said second material to form a reaction product on atleast the surface of said support, said support having a lower surfacearea than the surface area of the interspersed product of said dihalideand said second material; and (b) exposing at least the surface of saidsupport to a polymerization-active, liquid titanium compound to form asolid, titanium-containing catalyst component by bonding the titaniumcompound to at least the surface of said titanium-free catalyst support,wherein the quantity of titanium exposed to said catalyst support andthe quantity of titanium in said catalyst component are substantiallyequal.
 6. The method of claim 5, further comprising the step of exposingsaid titanium-free, solid, particulate catalyst support to a secondorganic electron donor compound prior to, simultaneously with or afterexposure to said liquid titanium compound, said second organic electrondonor compound selected from those compounds capable of forming areaction or addition product with said liquid titanium compound and notbeing detrimental to polymerization.
 7. The method of claims 5 or 6,wherein said magnesium or manganese dihalide is interspersed with saidsecond material prior to exposure to said first organic electron donorcompound.
 8. The method of claim 7, characterized by cocomminuting saidmagnesium or manganese dihalide and said second material, said secondmaterial being substantially isostructural with said magnesium ormanganese dihalide; and then cocomminuting the interspersed mixture ofsaid magnesium or manganese dihalide and said second material with saidfirst organic electron donor and generating a reaction by-productvolatile under the reaction conditions.
 9. The method of claim 5 whereinsaid first electron donor compound is characterized by having at leastone functional group selected from those organic functional groups whichwill produce at least one volatile reaction product with said secondmaterial under the conditions employed in the production of saidcatalyst component.
 10. The method of claim 6 wherein both of said firstand said second organic electron donor compounds are selected from thegroup consisting of organic compounds containing at least one atom ofoxygen, sulfur, nitrogen or phosphorous to function as the electrondonor.
 11. A method of producing a solid, particulate catalyst componentsuitable for use in alpha-olefin polymerization comprising:(a)co-comminuting a particulate material suitable for use in alpha-olefinpolymerization with a solid material different from but substantiallyisostructural with said particulate material to intersperse saidparticulate material in said solid material to form an intimateadmixture, the first particulate material being selected from the groupcomprising the Group IIA and IIIA salts and the salts of the multivalentmetals of the first transition series with the exception of copper, andthe solid material being selected from the group comprising the GroupIIIA salts; (b) exposing an organic electron donor compound to saidintimate admixture and reacting at least a portion of said electrondonor compound with at least a portion of the surface of said intimateadmixture to reduce the surface area of said intimate admixture andproduce a catalyst support; and (c) exposing said catalyst support to apolymerization-active, transition metal compound capable of being boundat least on the surface of said catalyst support to form a solidcatalyst component, wherein the quantity of transition metal compoundpresent in said catalyst component is substantially equal to thequantity of transition metal compound exposed to said support in thepreparation of said catalyst component.
 12. The method of claim 11,wherein said transition metal compound is a liquid titanium compound.13. The method of claim 12, wherein the exposing steps are performed byco-comminuting said electron donor compound with said intimate admixtureand then co-comminuting said liquid titanium compound with saidtitanium-free catalyst support.
 14. The method of claim 12, furthercomprising the following step after step (b) and before step(c):co-comminuting said titanium-free catalyst support with a secondorganic electron donor compound, the molar ratio of said second electrondonor compound to said titanium compound being equal to or greater thanone.
 15. The method of claim 12, wherein said titanium compound is aliquid complex or a solid complex of a liquid titanium compound with asecond organic electron donor compound, wherein the molar ratio of saidsecond electron donor compound to said liquid titanium compound isgreater than or equal to one.
 16. A solid titanium-containing catalystcomponent suitable for use in alpha-olefin polymerization, producedby:(a) forming a titanium-free, solid particulate support by:(i)interspersing a titanium-free particulate material suitable for use inalpha-olefin polymerization with a second solid material substantiallyisostructural therewith to produce an intimate admixture or solidsolution, the first particulate material being selected from the groupcomprising the Group IIA and IIIA salts and the salts of the multivalentmetals of the first transition series with the exception of copper, andthe solid material being selected from the group comprising the GroupIIIA salts; and (ii) exposing an organic electron donor compound to saidintimate admixture or solid solution under conditions to react at leasta portion of said organic electron donor compound with said secondmaterial at least on the surface of said intimate admixture or solidsolution to produce a titanium-free, solid, particulate support having alower surface area than said intimate admixture or solid solution; and(b) exposing said particulate support to a polymerization-active,titanium compound capable of being bound at least on the surface of saidsupport to form a solid, titanium-containing catalyst component having asurface area less than about one square meter per gram, wherein thequantity of titanium present in said catalyst component is substantiallyequal to the quantity of titanium exposed to said support in thepreparation of said catalyst component.
 17. A solid, particulatecatalyst component suitable for use in alpha-olefin polymerization,comprising:(a) a core of an interspersed admixture of first and secondmaterials, said first material being selected from the group consistingof a magnesium dihalide or a manganese dihalide suitable for use inalpha-olefin polymerization, and said second material beingsubstantially isostructural with said first material and being selectedfrom the group comprising the Group IIIA salts; (b) a reaction producton at least the surface of said core, said reaction product having beenformed in situ by a reaction between the second material and a firstorganic electron donor compound during co-comminution of said organicelectron donor compound with the previously-formed core; (c) optionallya second organic electron donor compound on said core, wherein saidsecond electron donor compound is suitable for use in the polymerizationof alpha-olefins to enhance the stereoregularity of the resultingpolymer; and (d) a polymerization-active transition metal compound boundon said core in a quantity substantially equal to the quantity oftransition metal compound exposed to said core during the production ofsaid catalyst component,said catalyst component further characterized byhaving a specific surface area less than about one square meter pergram.
 18. The solid catalyst component of claim 17, wherein said firstand second electron donor compounds are selected from the groupconsisting of organic compounds (i) containing at least one atom ofoxygen, sulfur, nitrogen or phosphorous to function as the electrondonor atom and (ii) characterized by having at least one moity selectedfrom those organic moities which will produce at least one volatilereaction product with said second material under the condititonsemployed in the production of said catalyst component.
 19. The solidcatalyst component of claim 18, wherein said second material is selectedfrom the aluminum trihalides, said first electron donor compound isselected from the aryl alkyl ethers, said second electron donor compoundis selected from the alkyl esters of the aromatic carboxylic acids andsaid polymerization-active transition metal compound is selected fromthe titanium tetrahalides.
 20. The solid catalyst compound of claim 18,wherein said first and second materials are magnesium dichloride andaluminum trichloride, said first and second electron donor compounds aremethyl phenyl ether and ethyl benzoate and said polymerization activetransition metal compound is titanium tetrachloride.